1. Field of the Invention
The invention relates in general to a wireless telecommunication device, and more particularly to a wireless telecommunication device which reduces noise interference towards an antenna.
2. Description of the Related Art
For a wireless telecommunication device such as a hand-held mobile phone, external static electricity is mainly originated from the fingers. It is easy for a person to carry static electricity especially under a cold and dry environment. When a user touches a button with his/her finger which carries static electricity, static electricity will be transmitted to the button from the tip of the finger. Therefore, the interference of electrostatic discharge (ESD) may be happen and harmful to the wireless telecommunication device inside an electronic element.
To prevent the interference of external static electricity, conventional wireless telecommunication device has a grounded conducting layer disposed under the button of a mobile phone. The conducting layer can discharge the instant static electricity originated from external sources to provide sufficient electrostatic discharge (ESD) and maintain electrical characteristics of the mobile phone stable.
However, the conducting layer for preventing external static electricity is like a shield to high frequency noises generated by a printed circuit board inside a wireless telecommunication device. This shielding effect will incapacitate high frequency noises to penetrate the conducting layer and be radiated along a direction perpendicular to the conducting layer, so the high frequency noise will gather around and be radiated from the edge of the conducting layer.
Consequently, the wireless sensitivity of the antenna disposed adjacent to the edge of the conducting layer will be greatly affected. A poor wireless sensibility affects the performance of an electronic telecommunication device greatly and is thus highly undesired by designers.